Because we have access to metadata that Google's naive crawler does not, we enjoy certain advantages when building a custom search. Certainly we can offer bells and whistles on the Super Search page that Google's advanced search can't match — they can't do filtering by author, ranking by node reputation, and so on.

I am confident that our users would find a KinoSearch-based Super Search considerably more usable than the current version, and that this would make them very happy. Programmers like to tweak tweak tweak. :) As a bonus, I also suspect that we can provide simple search results superior to what Google can offer, and certainly better than what we have now. It will be interesting to compare search results before and after we factor node rep into our ranking algorithm.

Whether or not it is worthwhile to maintain custom indexing and search for a public site depends on the site's size and the demands of its user-base. I expect that with several hundred thousand pages and extremely sophisticated users, we're well past the threshold. My guess is that the time it takes to maintain full-text search, including an advanced search interface, will be fully justified by a collective productivity increase. :)

SEO improvements to help web search engine spiders should probably be implemented regardless because increasing this site's visibility will aid people seeking answers to Perl questions from outside. However, I understand the powers-that-be have had good reasons for clamping down on spider access, historically.